1. Field of the Invention
The present invention relates to a semiconductor device including two or more substrates.
2. Description of the Related Art
Large numbers of electronic components are used in semiconductor devices which have been developed in recent years, in order to realize higher performance. The numbers of substrates for use in mounting such electronic components tend to be increased, although the mounting densities of respective substrates have been increased. On the other hand, there are requirements for reduction of the sizes of semiconductor devices. To cope with these requirements, substrates have been stereoscopically assembled, in order to increase the mounting densities.
In cases where substrates are stereoscopically assembled, it is necessary that, to a substrate forming a base (hereinafter, referred to as a “main substrate”), other substrates (hereinafter, substrates secured to the “main substrate” will be referred to as “sub substrates”) are secured.
However, in order to stabilize the position and the attitude of the sub substrates relative to the main substrate in assembling them, there is a need for dedicated jigs. In cases of assembling using dedicated jigs, there is induced inconvenience of increase of the number of assembling processes. Further, it is also possible to employ a method which uses additional securing members, but such a method induces the problem of increase of assembling processes due to the increase of the number of components and, further, induces the problem of increase of the material cost by an amount corresponding to the additional components.
The present invention was made in view of the aforementioned circumstances and aims at providing a semiconductor device which can be assembled through an assembling method capable of assembling for securing sub substrates to a main substrate without increasing the number of components and the number of processes.